The John Deere 4250 was manufatured with two types of transmissions. One transmission was the quad shift which requires the clutch to shift between some gears. The other transmission was a full powershift transmission which requires no shifting between gears and has an inching pedal instead of a clutch.

If you can tell me which transmission your tractor utilizes, I would be happy to investigate further.

If you don't use the clutch your tractor is equipped with a powershift transmission. If you are missing multiple gears in your shifts the problem is likely one of the shift solenoid that controls one of the many clutches inside your transmission. If you are not familiar with the workings of your transmission, I suggest you take the tractor to your nearest repair shop to have a look at.

If you have any other questions regarding your problem, I would be happy to help. If you would be able to leave a positive feedback for the service I provided you today, I would really appreciate that.